Gauge and control apparatus for liquid containers



May 28, 1940- G. E. Ewl-:RTz 2,202,197

GAUGE AND CONTROL APPARATUS FOR LIQUID CONTAINERS Filed DeC. 3, 1955 f fn o m 0 Patented May 28, 1940 GAUGE AND CONTROL APPARATUS FOR LIQUIDCONTAINERS Gordon E. Ewertz, Elizabeth, N. J.

Application December 3, 1935, Serial No. 52,735

2 Claims.

'I'his invention relates broadly to a gauge and control apparatus forliquid containers.

'Ihe primary object of the invention is to ,provide a gauge and controlapparatus for liquid containers, as, for example, hydraulic systems suchas hard tank fuel systems, or other liquid containers wherein may befound a liquid supporting a gas, such as air or any other gas, or, a

liquid supporting other non-mixing liquids, said gauge and controlapparatus being combined one with another or not, as may be desired.

Another object of the invention is to provide a safe and effectiveapparatus for gauging one or more liquids Within a container and, ifdesired, for controlling the flow of said liquids into and out of saidcontainer.

Another object of the invention is to provide an apparatus, that may belocally and/or remotely operated and observed; that makes possible theaccurate control of a hydraulic system Without the necessity ofintroducing hydrostatic balance to prevent over-delivery orover-filling, and, furthermore, makes possible a direct pressurehydraulic system.

Still another object of the invention is to provide an apparatus whichhas no moving parts within the container, and which is independent ofthe Baume of the liquid or liquids in the container.

An important consideration in the operation of the apparatus is thesubstantial elimination of electrolysis in an electrically actuatedmechanisrn. It is, therefore, an object of this invention to utilize avacuum tube, or tubes, in the structure of the apparatus in such amanner that hazards caused by electrolysis will be eliminated.

The invention consists in a gauge and control apparatus for liquidcontainers, said gauge and control apparatus being combined one withanother or not, as set forth in the following speciflcation andparticularly as pointed out in the claims thereof.

The figure of the drawing is a diagrammatical illustration of a gaugeand control apparatus em. bodying my invention and as applied to a hardtank fuel system, said gauge, and control apparatus being adapted to becombined one with another or not, as may be desired.

In the drawing, I represents a closed container, preferably the fueltank of a hard tank fuel system, and 2 represents water in said tank toa level indicated at 3 above which the tank is filled with fuel oil 4.The oil 4 is supplied to the tank I through a fuel supply pipe 5 inwhich are hand-operated valves 6 and 'I. A feed pipe 8 delivers the oilwithin the tank I from the top thereof to a burner or burners well knownin the art and utilizing oil as a fuel, said burners being located asmay be desired. A solenoid valve 9 of well-known construction andactuated in a manner hereinafter to be described is provided for thepipe 8.

The water 2 is supplied to the tank I from a tank I0 of Well-known typepositioned at a suitable height above said tank I thereto by a pipe IIwhich discharges into the tank I at a point adjacent to the bottomthereof.

The tank I0 receives its supply of water under pressure from a suitablereservoir for said water through a pipe I2, and delivers gravity to thetank I. A hand-operated valve I3 is provided for the pipe II. Adischarge pipe I4 for the water within the tank I is connected to thepipe I I at I5 between said tank and the valve I3. An overflow pipe I6for the tank I0 connects with the pipe I4. A weighted, lever-operatedgate valve I1 of well-known construction is provided for the pipe I4, alever I8 of said gate valve being released to permit the valve to closeby means of a solenoid release catch I9 actuated 25 in a mannerhereinafter to be described.

That portion of the mechanism of the invention which constitutes thegauge and control mechanism therefor, and which may be located at apoint adjacent to the tank I, or at a point remotely removed therefrom,if it is so desired, is as followsz-Mounted Within the tank I are aplurality of electrodes 2|), 2|, 22, 23, 24 and 25 all insulated fromeach other and from the tank I. As illustrated, these electrodes consistof insulated rods of different lengths having bare lower extremitiesexposed to the liquids in the tank at .different levels therein, but itis evident that said electrodes may be of any desired constructionprovided they have electric contact points embodied therein which areexposed to the liqo uids and are located at different elevations in thetank and are insulated therefrom, and they may consist of plugs mountedat different elevations in the side of the tank, if it is so desired,without departing from the spirit of the invention. 'I'he electrode 20is common to all of the circuits which include the other electrodes, andthe tank I itself may be used as a common lead in place of the electrode20, if it is so desired.

The electrode 20 is connected by a wire 26 with the negative pole of agrid battery 2l. The electrodes 2|, 22, 23, 24 and 25 are connected byWires 28, 29, 30, 3| and 32 respectively with contact members 33, 34,35, 36 and 31 respectively 55 and connected 10 said water by 15 of a twobank rotary switch 38. Other contacts 39 and 40 of said switch 38 areelectrically connected to the contacts 33 and 31 respectively. An arm 4Iof the switch 38 is electrically connected by a wire 42 to the grid 43of a vacuum tube 44. Another arm 45 of the rotary switch 38 upon theopposite side thereof from the arm 4| is movable in unison with said arm4I, but is insulated therefrom. The arm 45 of the switch 38 engagescontact members 33', 34', 35', 36', 31', 39' and 40 oppositely disposedto the contacts 33, 34, 35, 36, 31, 39 and 48 respectively, butindependent thereof and insulated therefrom. The contact 39 is connectedby a wire 46 to the solenoid release catch I9 for the gate valve I1, andthe contact 40' is connected by a wire 41 to the solenoid valve 9. Thearm 45 is electrically connected by a wire 48 to a battery 49 whichfurnishes power for visible and audible signals hereinafter to bedescribed.

The vacuum tube 44 is well known in the art and embodies therein a grid43, a filament 58 and a plate I. Current for the filament 50 is providedby a battery 52 which is connected thereto by wires 53 and 54. A switch55 is provided in the wire 53 and the latter is also connected to thegrid battery 21. Current for the plate 5I is provided by a battery 56,one side of which is connected by a wire 51 to the wire 54, and theother side is connected by a wire 59 to the plate 5I through a relay 58.

The relay 58 opens and closes local signal circuits, one of whichincludes a red light 60 and the battery 49, while another includes agreen light 6I and the battery 49. An audible signal as, for example, abell alarm 62 may be connected into both of these local circuits bywires 63 and a switch 64. The red and green lights are connectedtogether and one side of the light 60 is connected by a wire 65 to thesolenoid release catch I9, and one side of the light 6I is connected bya wire 66 to the solenoid valve 9. In the operation of the apparatus thelights 60 and 6I are located in separate circuits. The bell 62 andswitch 64 are connected one to another, and to the battery 49, by thewire 63, and said battery furnishes the power for said bell and for thelights 60 and 6I.

The general operation of the apparatus hereinbefore specificallydescribed is as follows: Assuming first that the apparatus isfunctioning as a control device, and that fuel oil 4 in the tank I isbeing discharged to burners not illustrated in the drawings, butwell-known in the art, the valves 6 and 1 in the fuel supply pipe 5 areclosed and the solenoid valve 9 in the supply pipe 8 to the burners isopen. At this time, also, the valve I1 is closed and the valve I3 isopen, thereby permitting the oil in the tank to feed to the burners andalso providing the necessary water to displace the fuel oil consumed.

Under these conditions, furthermore, the arms 4i and 45 of the switch 38are at discharge position in engagement with the contacts 40 and 40'respectively of said switch. As the level of the water 2 in the tank Irises and the amount of oil 4 above said water decreases, the water will'iinally contact with the exposed lower extremity of the electrode 25,whereupon an electric circuit will be closed through said water betweenthe electrodes 20 and 25. As the leads 26 and 32 of the electrodes 20'and 25 respectively are connected to a negative potential and the grid43 of the vacuum tube 44, when said electrodes are in water, thenegative potential will be applied to ,by the solenoid release catch I9.

the grid of said vacuum tube and the plate current will be cut to, ornearly to, zero. At this time the relay 58 in the plate circuit will beactuated to cause the green light to be illuminated and also cause thebell alarm 62 to be sounded provided the latter is out into the localcircuit with the green light at the switch 64. At the same time that theelectric circuit is closed through the water between the electrodes 20and 25, the solenoid valve 9 is closed to shut oif the discharge of oilfrom the tank I and make it impossible for water to follow the oil tothe burner.

The operation of the apparatus as a control device in filling the tank Iwith oil is as follows:

First set the switch arms 4I and 45 at the fill position in engagementwith the contacts 39 and 39' respectively of the switch 38, close thevalve I3 in the water supply pipe line II, and set the gage valve I1 inopen position, at which time the operating lever I8 of said valve willbe held open Open the valves 6 and 1 in the fuel supply pipe 5. Thesolenoid valve 9 is closed. As the oil 4 enters the tank I through theVsupply pipe 5, the water 2 will be forced outwardly from said tankthrough the pipes II and I4 and Valve I1 to be discharged at anysuitable location, as into a sewer, and the level 3 or interface betweenthe oil and water in the tank I will nally be forced below the exposedlower extremity of the electrode 2|, at which time said lower extremitywill be located in oil while the exposed lower extremity of theelectrode will still remain in water, thereby breaking the electriccircuit therebetween. A zero potential will now be applied to the grid43 of the vacuum tube 44 and current .will flow in the plate' circuitwith the result that the relay 58 will be actuated to cause the redlight 60 to be illuminated and also cause the bell alarm 62 to besounded provided the latter is cut into the local circuit with said redlight at the switch 64. At this time the solenoid release catch I9 isactuated to release the lever I8 of the valve I1 allowing the weightthereon to close said valve. With the wa.- ter overow closed off it isimpossible for any more oil to enter the tank I and also impossible forany of the oil to follow the water to the sewer. Under these conditions,furthermore, the solenoid valve 9 will operate to permit the oil to iiowto the burner through the pipe 8 when the valve I3 is again opened andthe switch 38 is set for discharge.

The operation of the apparatus as a gauge in ascertaining the quantityof oil in the tank I is as follows: The arms 4I and 45 of the switch 38are moved from empty towards full, or vice versa, to successively engagethe arm 4I with the contacts 33, 34, 35, 36 and 31, and the arm 45 withthe contacts 33', 34', 35',v 36' and 31 of said switch. At this time thesolenoids for the valve 9 and for the catch I9 are automaticallydisconnected from the electric circuits. As the arms 4I and 45 are movedinto contact with the various contacts above mentioned, the green light6I or the red light 60 will be illuminated as occasioned by the closingor the opening of the various electric circuits between the electrodes 2I, 22, 23, 24 and 25, and the electrode 20 which is common to all of thecircuits including these electrodes. When the exposed lower extremitiesof -the electrodes above mentioned are in water the circuits will beclosed and the green light 6l will be illuminated, but if any one of theextremities of said electrodes 2l, 22, 23, 24 or 25 is in oil and theelectrode 20 is in water the electric circuits will be open and the redlight 80 will be illuminated. 'Ihe ilneness of the reading of thecontents of the container by the gauge is deter mined by the number ofelectrodes provided in the tank l, and it is evident that it isincreased by increasing the number of said electrodes, in which eventthe exposed contact portions thereof will be spaced closer together.

One or more vacuum tubes with any suitable power supply well known inthe art may be utilized as may be desired, the basic principle beingthat a change of level of the liquid or liquids to be gauged causes achange of grid bias. This change of grid bias changes the amount ofcurrent flowing in the plate circuit of the vacuum tube, and this changeof plate current is utilized to operate visible and/or audible signalsor alarms, to control the ow of liquid or liquids into or out of acontainer, or to control the operation of any other desired apparatus.

While it is possible to use a positive grid potential (bias), to do sowould mean that there would be a grid current owing through the tank.

By setting the alarm switch 64 for either oil or water, and setting theswtch 38 at the point alarm is desired, the bell l2 will ring when thewater or oil reaches that level in the tank. This may be used as awarning that more oil is needed.

It will be understood that the contact members Il', Il', 3B', 38' and,31' of the switch 38 that have no wires connected thereto perform nofunction in the operation of the device other than to contribute to thesmooth operation of the switch arm 45.

I claim:

1. Liquid level responsive means having, in combination, a container fora liquid and at least one other separate hazardous fluid, said fluidshaving different electrical resistances, a vacuum tube, sources ofelectrical potential to energize said tube, two electric contactsinterposed in the grid circuit of the vacuum tube, at least onepositioned at a predetermined level within said container exposed tosaid fluids, there being a negative potential applied to said gridthrough the fluid of least electrical resistance lwhen both of saidcontacts are immersed therein, and means responsive to change in theplate circuit of the vacuum tube.

2. Liquid level responsive means having, in

combination, a container for water and a nonmixing hazardous fluid, thelatter being a nonconductor of electricity, a vacuum tube, sources ofelectrical potential to energize said tube, electric contacts interposedin the grid circuit of the vacuum tube and positioned at dierent levelswithin said container exposed to said fluids, there being a negativepotential applied to said grid through said water when two of saidcontacts are immersed therein, and means responsive to change in theplate circuit of the vacuum tube.

GORDON E. EWERTZ.

